• synonyms


noun, plural cha·la·zas, cha·la·zae [kuh-ley-zee] /kəˈleɪ zi/.
  1. Zoology. one of the two albuminous twisted cords which fasten an egg yolk to the shell membrane.
  2. Botany. the point of an ovule or seed where the integuments are united to the nucellus.
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Origin of chalaza

1695–1705; < New Latin < Greek: hail, lump
Related formscha·la·zal, cha·la·zi·an [kuh-ley-zee-uh n] /kəˈleɪ zi ən/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for chalaza

Historical Examples of chalaza

  • Seeds larger than Aestivalis, pear-shaped; chalaza roundish.

    The Grapes of New York

    U. P. Hedrick

  • Chalaza, the place where the coats and the kernel of the ovule blend.

  • Orthotropous ovule of Buckwheat: c, hilum and chalaza; f, orifice.

  • Campylotropous ovule of a Chickweed: c, hilum and chalaza; f, orifice.

  • The chalaza is at the insertion or base, the foramen or orifice is at the apex.

British Dictionary definitions for chalaza


noun plural -zas or -zae (-ziː)
  1. one of a pair of spiral threads of albumen holding the yolk of a bird's egg in position
  2. the basal part of a plant ovule, where the integuments and nucellus are joined
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Derived Formschalazal, adjective

Word Origin for chalaza

C18: New Latin, from Greek: hailstone
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

chalaza in Science


Plural chalazae (kə-lā) chalazas
  1. One of two spiral bands of tissue in an egg that connect the yolk to the lining membrane at either end of the shell.
  2. The region of a plant ovule that is opposite the micropyle, where the integuments and nucellus are joined.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.